FIGS. 1 and 2 show a typical conventional brake means 2 for a wheel 1 in a caster.
The brake means 2 constitutes a bracket 21, a load seat 22, a brake body 23, and the wheel 1.
The bracket 21 is a reversed-U shape member and includes two side walls 211 and a top wall 213. The side walls 211 have two lower pivot holes 2112, a front shaft 2114 and a rear shaft 2116. The top wall 213 has an upper pivot hole 2132. The wheel is pivotly held by a bolt between the lower pivot holes 2112.
The load seat 22 includes a load plate 221, an upper cap 222 and a lower cap 223. The upper and lower caps 222 and 223 are mating against each other at two opposite side of the upper pivot hole 2132. In the caps 222 and 223, there are a plurality of steel balls 224 located thereon (also referring to FIG. 3). The load plate 221 is located above the upper cap 222. The lower cap 223 has slots 225 radically formed at the bottom. The load seat 22 may be freely rotating.
The brake body 23 includes a friction plate 231 and a pedal 232. The friction plate 231 is a&lt;shaped member including an upper spring plate 2311 and a lower spring plate 2312. The upper spring plate 2311 has a brake tooth 2312 formed at one end. The pedal 232 has an ellipse cam 2322 formed at one end thereof which is engaged with the rear shaft 2116. The friction plate 231 has a front end pivotally engaged with the front shaft 2114 (shown in FIG. 3). The cam 2322 is held on the pedal 232 firmly.
Referring to FIG. 3, in the conventional caster the brake means 2 is engaged with the load plate 22 and is located at a lower portion of the caster. For braking the caster, the pedal 232 is pressed downward which turns the cam 2322 which in turn pushes the upper and lower spring plates 2311 and 2312 outward against each other until the brake tooth 2312 engaging with the slot 225 and the lower spring plate 2312 pressing against the wheel 1 for preventing the wheel from moving. The wheel 1 will also be prevented from turning (due to engagement of the brake tooth 23112 with the slot 225) (shown in FIG. 4). For releasing the brake, the pedal 232 is moved upward to return the cam 2322 to its initial position (FIG. 3). The upper and lower spring plates 2311 and 2312 are disengaged respectively with the slot 225 and the wheel 1. Then the wheel 1 may be moved and turned again.
There are disadvantages in the conventional caster mentioned above. For instance, when releasing the brake, the pedal 232 shall be moved up by people, mostly by hand. It is awkward for people to bend down to reach the pedal. The hand get smeared easily. Moreover the brake means 2 usually is mounted on the bracket 21. When the wheel 1 changes direction, the pedal 232 also change direction and might become non-accessible to users (e.g., being swivelled under the cart under which the casters are mounted). Trying to get the pedal moved out for people use is troublesome and could easily cause human injury or cause the cart to bump against other object or wall, and result in damage.